prob n stats

Survival of patients with lung cancer after diagnosis 1) (2) (3) (4) (5) (6) (7) (8) Interval Alive at Died Withdrew Effective Proportion Proportion Cumulative Since Beginning during during Number Who Died Who Did Proportion Beginning of Interval Interval Exposed during Not Die Who Treatment Interval to Risk of Interval during Survived ( year) Dying Interval from during Enrollment Interval to End of Interval: Cumulative Survival X d 9 , Px P 1 500 130 55 2 315 85 49 3 181 69 37 4 75 45 15 Note: Carry your calculations to three decimal places. a) What is the effective number of people exposed to risk of dying during the first year? b) What is the proportion of people who died in the second year? c) What is the proportion of people who survived in the third year? d) What is the probability that a person enrolled in the study will survive to the end of the fourth year? 3